The invention relates to targeted delivery technology. More particularly, the invention relates to a delivery system targeting sigma receptors over-expressed cells.
Anti-cancer drugs presently in clinical use have low therapeutic windows, resulting in serious side effects. Therefore, a targeted delivery system for delivering those toxic drugs to target cells is needed.
Nanoparticle delivery systems, such as liposomes, polymer-based delivery systems, or emulsions, are unable to target to specific cells. Therefore, targeted ligands that can modify the nanoparticle delivery systems are required for developing targeted delivery systems. However, antibodies, the most common used ligands in targeted drug delivery may cause serious immune response after systemic injection and this would be a potential problem.
Small molecule ligands with no immunogeneicity and ease for scale up production are more desirable for modifying delivery systems, thus are more potential for targeted delivery systems development compared to antibodies.